Process of treating petroleum oils with a copper soap and of producing the copper soap



c. o. HoovER 2,471,153 PROCESS OF TREATING PETROLEUM OILS WITH A COPPERMay 24, 1949.

SOAP AND OF PRODUGING THE COPPER SOAP Original Filed Oct. 2, 1946 2Sheets-,Sheet l C. O. HOOVER May 24, 1949.

PROCESS OF TREATING PETROLEUM OILS WITH A COPPER SOAP AND OF PRODUCINGTHE COPPER SOAP Original Filed 001;. 2, 1946 2 Sheets-Sheet 2 PatentedMay 24, 1949 UNITED STATES @ATENT OFFICE PROCESS F TREATING PETROLEUMOILS WITH A COPPER SOAP AND OF PRODUCIN G THE COPPER SOAP Charles O.Hoover, Houston, rex., assignor to Air Reduction Company, Incorporated,New York, N. Y., a corporation of New York Original application October2, 1946, Serial No. 7 00,823. Divided and this application April 25,1947, Serial No. 743,886

15 Claims.

fixing certain sulfur compounds, present in the naphthenate in thetreatment of crude oil, as described above, or naphthenic acid liberatedfrom crude petroleum oil during the distillation or fractionationthereof is first lconverted into an alkali-metal naphthenate, such assodium naphthenate, and the alkali-metal naphthenate so produced, or analkali-metal naphthenate from any other source, is reacted with a coppersalt, preferably in the presence of a small amount crude petroleum oilto prevent formation of delof hydrocarbon oil which acts as a solventfor eterious sulfur compounds in the products of the Water-insolublecupric naphthenate prodistillation of the oil. duced as a result of thedouble decomposition This application is a division of my applicaof thesodium naphthenate and copper sulfate. tion Ser. No. 700,823 filedOctober 2, 1946. The process preferably is carried out as a cyclic It iswell known that most crude petroleum one in which the cupric naphthenateformed by oils contain sulfur in the form of hydrogen sulreaction oi thealkali-metal naphthenate with de or in more complex forms, the exactnatures the Coppel Sulfate S used in 'Gllc treatment 0f of which are notknown. When such crudes are hydrocarbon OilS aS described abcVe, and'the distilled, reaction occurs Which results in the naphthenic acidcontained in the distillate from formation of mercaptans and disuldes,which the distillation or fractionation chamber rst is compoundsgenerally are not found in crude reacted with an alkali-metal hydroxideto form petroleum oils. an alkali-metal naphthenate which subsequentlyIn my co-pending application Ser. No. 600,646, is reacted with thelcopper' Salt to form more Patent No. 2,467,429, filed June 20, 1945, Ihave cupric naphthenate. Thus, the naphthenic acid disclosed a methodfor the treatment of crude liberated during the treatment 0f the crudepepetroleum oil to stabilize or otherwise modify sulfur compounds, otherthan hydrogen sulfide, which may be present so that upon subsequentdistillation of the crude petroleum oil the sulfur compounds containedtherein do not decompose J or react to produce mercaptans, disuldes orother deleterious sulfur compounds in the distillates. In accordancewith the method disclosed in that application, cupric naphthenate isadded to and intimately mixed in relatively small Thus, not only iS thenaphthenc acid liberated amounts With the crude petroleum oi1 prior toduring the treatment of the oil recovered and the distillation orfractionation thereof. The adused as one of the materials for formingmore dition of cupric naphthenate tothe crude pecupric naphthenate to beused, but the copper troleum oil stabilizes the sulfur compounds, otherproduct of the decomposition is used to form the than hydrogen suinde,contained therein so that Copper Salt used in the reaction with theSodium upon subsequent distillation or fractionation of naplltllenate-Therefcle, the DIGCSSS iS cyclic the crude petroleum oil they do notreact or debOtl'l With TGSDQC t0 0010961 and naphthen acid. compose toform mercaptans and disuldes. F01 a fuller and mcle completeunderstanding In the process of my aforesaid application, of theinvention reference is made to the acthe cupric naphthenate isdecomposed during the Compamng drawings in Which heat treatment of thecrude oil and yields naph- Fig. 1 is a flow sheet illustrating onemethod. thenie seid which passes oe with the distilietes. in which theprocess 0f the present invention Also, any nophthenie acid which ispresent in may be carried out in a Cyclic manner in conthe crudepetroleum oil, as such, will carry nection with the treatment of crudepetroleum through the distillation or fractionation chamoil with cupricnaphthenate, and ber and pass oil with the distillates, Fig. 2 is a flowsheet of a slightly modied ar- The present invention contemplates aprocess rangement of producing copper soaps, such as copper Referringfirst to Fig. 1, a charge of crude. naphthenates, in which naphthenicacid such as petroleum oil passing through a conduit l, to-. thatresulting from the decomposition of cupric l troleum is recovered andre-fused.

The present invention also contemplates a process in which the copperproduct resulting from the decomposition of the cupric naphthenate,during the treatment of the hydrocarbon oil containing the same, is usedas a source material for forming the copper salt, which in turn may beused for reaction with the alkalimetal naphthenate to form the cupricnaphthenate.

gether with a small amount of cupric naph thenate introduced through aconduit 2, is pumped by a pump 3 through a charge heater 4 Where thetemperature of the crude petroleum oil is raisedto its flashing point,for example, about 750 F. The thus heated crude oil, together with thecupric naphthenate contained therein, is then introduced into the lowerportion of a fractionation column 5, whereupon ,the petroleum oil ashes,forming a vapor phase consisting of distillates and naphthenic acidresulting from decomposition of the cupric naphthenate, and a liquidphase consisting of fuel oil'which carries the copper product of thedecomposition of the cupric naphthenate. The copper product and the fueloil settle to the bottom ofthe column and are withdrawn as hereinafterdescribed. Thevapor resulting from the flashing of the hot charge ofcrude oil may be fractionated into as many fractions as desired. Asshown in Fig. l, is divided into a light gas and gasoline fraction whichis withdrawn from the top-of the column 5 through a conduit 6, a heavierfractionA of light distillates which is withdrawn ata lower level fromthe column, through'a conduit l, and a still heavier fraction consistingessentially of gas oii which is Withdrawn from a still lower portion ofthe columnthrough a conduit ii. The fractions withdrawn-through theconduits e, l and i3 will contain *varying amounts of the naphthenicacid resulting from the decomposition of the cupric naphthenate, and, ifthe crude oil is of the naphtheme-base type, from the presence ofnaphthenic acid present, as such in the original crude oil. However,most of the naphthenic acid will be contained in the gas oil fractionwithdrawn through conduit 8. The fractions withdrawn through theconduits 6, 'i and S may be passed through condensers 9, Ill and I! inaccordance with the usual practice.

In accordance with the present invention any oneor all of-the fractionswithdrawn through the-conduits B, 'F 'and 8 Vmay be treated with analkali-metal hydroxide, preferably molten caustic, to-'form analkali-metal naphthenate, which subsequently is converted to cupricnaphthenate. As shown in Fig. l, the gas oil fraction withdrawn throughthe conduit 8, which contains a relatively large-percentage of thenaphthenic acid resulting from decomposition of the cupric naphthenateused-'in the treatment of the-oiLis passed through a neutralizer I2where it is caused to react with an alkali-metal hydroxide, preferablysodium hy droxide, supplied in the form of a concentrated solution ofabout 45 to 50 B. from a container I3-by means of a pump I4 and conduitI5. On introduction of the caustic solution into the neutralizer- I2lthe water content thereof vaporizes, and leaves the caustic in themolten state. The neutralizer I2 is maintained substantially filled Withchains or some inert material which vwill causea large surface contactbetween the molten caustic and the hot oil vapors containing thenaphthenic acid. As thehot gas oil vapors and naphthenic acid-rise inthe neutraliser i2 countercurrent to the downward flowing molten causticthe naphthenic acid contained in them comes into. intimate contact withthe caustic with the resulting formation of sodium naphthenate andwater. The sodium naphthenate which is thus formed has a higher boilingpoint than the gas oilandsettles to the bottom of the neutralizer as aliquid. The amount of sodium hydroxide introducedinto the neutralizer I2is equal to or slightly 'more .or less than the stoichiometricequivalent ofthe naphthenic acid contained in the gas oil vapors. Thepressure in the neutralizer is not important; it may be that normallyprevailing in columns where gas oil vapors are fractionated.

In order to obtain more complete reaction betweenthe caustic and thenaphthenic acid, the sodium naphthenate and any unreacted caustic arewithdrawn from the bottom of the neutralizer i2 through a conduit I5 andpumped by a pump Il through a conduit I8 back to the upper portion ofthe neutraliZer through which it thus circulates. The conduit I8 isprovided with a valve I9. A conduit 20 is connected to the conduit I8between the pump Il and the vaive I9 which normally is so adjusted thata relatively small proportion of the sodium naphthenate constantly iswithdrawn through the conduit 2t. The gas oil freed of the naphthenicacid, and steam resulting from vaporization of the water formed duringthe reaction between the naphthenic acid.

sulfate, or othercopper salt, such as thentrate; chloride, etc., intheform lof an aqueous solutiony introduced through a conduit 23 from asupply tank 2li. An agitator 25is Aprovided in the reaction chamber 22`and is operated at a speed suii'icient to impart lav gentle agitationto themixture undergoing reaction therein. If the sodium naphthenatewithdrawn through the conduit 20 contains any free caustic, it isneutralized before the sodium naphthenate is reacted with the coppersulfate.

In the reaction chamber 22, the sodium naphthenate reacts with thecopper sulfate to form sodium sulfate and cupric naphthenate. The sodiumsulfate may be withdrawn from the bottom of the reaction chamber 22through a conduit 26. The cupric naphthenate which is formed iswaterinsoluble but is oil-soluble. Ordinarily enough of the higherboiling constituents of the gas oil will be condensed and withdrawn fromthe neutralizer I2 along with the sodium naphthenate by entrainment todissolve the cupric naphthenate as fast as it is formed in the reactionchamber 22. The solution of cupric naphthenate in the gas oil, beinglighter than the aqueous solution of sodium sulfate, will form asupernatant layer on top of the aqueous sodium sulfate and willcontinuously pass over a launder 2 in the tank y22 and be withdrawnthrough a conduit 28.

If the copper sulfate solution supplied fromthe tank 2d is notsuiiiciently dilute to obtain sufficiently rap-idly reaction between andthe sodium naphthenate, additional water may beintroduced into thereaction tank 22 through a.

conduit 29.

The cupric naphthenate withdrawn from the` reaction tank 22 through theconduit 28 is cycled back through the conduit 2 and used for thetreatment of further amounts of crude petroleum oil in the manner moreparticularly described inv my aforesaid application.

The bottoms from the fractionation column 5' constitute thefuel oilfraction rand contain all, or at least most, of the copper productresulting from the-decomposition of the cupric Ynaphthe-A nateasdescribed4 above. The copper in such copper product ordinarily will bein the form of cuprous sulde, cuprous oxide, metallic copper, orinsoluble copper-sulfur compounds of unknown composition. The bottomsfrom the fractionation column containing the copperI product referred toabove is withdrawn through a conduit and passed by means of a pump 3l toa thickener or lter 32, which may be a hot-oil iilter, a thickener ofthe Dorr type or a thickener of lter of any other type which willseparate the hot fuel oil from the entrained copper product. Theseparated fuel oil is Withdrawn through a conduit 33 while the recoveredcopper product is withdrawn from the bottom of the thickener or lterthrough a conduit 34.

The copper product passing through the conduit 34 is delivered to atreater 35 Where it is converted to copper sulfate in any desiredmanner. This may be done by roasting, treatment with sulfuric acid or acombination of both steps. Ordinarily it is preferred to iirst roast thecopper product to convert the metallic copper content thereof to theoxide, in which form it is more readily acted upon by sulfuric acid. Theresulting copper sulfate is withdrawn through conduit 35 and passed tothe copper sulfate container 24 for reaction with more sodiumnaphthenate withdrawn from the neutralizer I2.

If the particular crude petroleum which is being treated is of thenaphthene-base type and contains a relatively high proportion ofnaphthenic acid, the amount of sodium naphthenate formed in theneutralizer I2 may be more than would be desirable to convert to cupricnaphthenate for re-use in the system. In such a case, any such excess ofsodium naphthenate may be withdrawn through a conduit 36 controlled by avalve 31; or the excess naphthenic acid may be permitted to remain inthe distillate, reacting only sufcient of the naphthenic acid with thecaustic to form the required amount of sodium naphthenate for subsequentconversion to cupric naphthenate. That may be done by restricting theamount of caustic available for reaction with the naphthenic acid in theneutralizer I2, by by-passing a portion of the hot gas oil vaporsthrough a conduit 8a controlled by a valve 8b. On the other hand, shouldthe amount of naphthenic acid contained in the crude petroleum oil beinsumcient to compensate for that lost by removal with lighter fractionsnot treated ,j

for the recovery of the naphthenic acid content thereof, such additionalamount of naphthenic acid as may be necessary may be introduced througha conduit 38.

In Fig. 1 only the gas oil fraction withdrawn from the lower portion ofthe fractionator or distillation column `5 is treated for recovery ofthe naphthenic acid and its conversion to cupric naphthenate. However,if desired, the fractions withdrawn through the conduits 6 and 'I alsocould be passed through neutralizers similar to the neutralizer I2 forconversion of the naphthenic acid content thereof to sodimu naphthenatewhich subsequently would be converted to cupric naphthenate as describedabove, such neutralizers being indicated in dotted lines at I2a and I2b,respectively.

In Fig. 2 there is disclosed a modied form of the invention in which theheated charge of crude petroleum oil containing the cupric naphthenateis first introduced into a flash drum 40. All of the fuel oil formed asa result of the flashing of the crude petroleum, and the copper productresulting from decomposition of the cupric naphthenate, settle to thebottom of the ash drum, as described in connection with the proci-l essas carried out with the apparatus of Fig. 1.

All of the vapors from the flash drum are withdrawn from the top througha conduit 4I and passed through a neutralizer I2 where the naphthenicacid content thereof is reacted with caustic to form sodium naphthenatein the manner described above. The hydrocarbon vapors and steamresulting from vaporization of Water produced in the reaction betweenthe caustic and sodium naphthenate is withdrawn from the top of theneutralizer I2 through a conduit 2| and passed into the lower end of afractionator 42 where they are fractionated into lighter and heavierfractions which are withdrawn through conduits 43, 44 and 45,respectively. Those fractions may be passed through condensers 9', I0and II', respectively, as is customary. In all other respects, theprocess represented by the ow sheet of Fig. 2 is identical with thatdescribed above in connection with the flow sheet of Fig. 1, and likereference characters, primed, have been used to designate like parts ofthe apparatus.

From the aforegoing, it will be apparent that the present inventionprovides a process for producing cupric naphthenate which preferablyforms a part oi' a cyclic process for the treatment of crude petroleumwith cupric naphthenate in which provision is made for the recovery ofthe copper content as well as the naphthenic acid content of the cupricnaphthenate treating agent, and their reaction to provide additionalcupric naphthenate which may be used for the treatment of additionalcrude petroleum. When used in connection with such a process for fixingsulfur compounds contained in the crude petroleum oil it has the furtheradvantage of improving the quality of the distillates which arerecovered due to the fact that the naphthenic acid and any other organicacids which are present in the distillates are removed.

While the invention has been particularly described in connection withthe production of cupric naphthenate from naphthenic acid or sodiumnaphthenate, it is to be understood that the process is equallyapplicable to the production of other copper soaps of water-insolubleorganic acids which are volatile and subsequently stable at thetemperatures to which the oil is heated, such as cupric oleate, orcupric tallate. Thus, if cupric oleate, for example, were used for thexation of sulfur compounds in the crude oil, oleic acid would resultfrom the decomposition of the cupric oleate in the fractionation columnf `which. could be reacted with the caustic in the neutralizer I2 toform sodium oleate, which subsequently vwould be converted to cupricoleate in the manner described above in connection with conversion ofsodium naphthenate to cupric naphthenate.

Also, the process is not necessarily limited to the production of cupricnaphthenate or similar cupric salts of water-insoluble organic acids,and would be equally useful for the production of cuprous naphthenate orother cuprous salts of water-insoluble organic acids. In order toproduce cuprous naphthenates or other cuprous salts of water-insolubleorganic acids it is only necessary that a heater 39, through which thecupric naphthenate may be bypassed and heated to a temperature suicientto cause its reduction to cuprous naphthenate, be inserted in theconduit 28.

While the charging stock introduced through the conduit I has beenreferred to as crude petro- I aufm st.

ieumicinit visfto :be:understoodzxhatiit mightxbe-r anyntnerstookl'vvhich'ritis desiredf-to'treat with;

cupric' naphthenatev for' the iixation .oi.` sulfur compounds containedthereinf- Variouslchan'ges maybe madein the procedure Without 'departingfrom. theinvention'or Isacriic;

ing-any of lthe advantages thereof.

I claim:

1.1 the-'process of treating petroleumoil With-l acopper-soapofaWater-insoluble organic acid containing `theorganic acidI resulting`from decomposi-ti'onfof the copper soap; the improvement' whichcomprisesl separately withdrawing th'ecopper-compound and the liberated-vaporsfcontain'- in'gtheprganic acid resulting from'the decompositionof the-copper soap'from the Zone of heat treatment passing withdrawnvapors into intimate lcontact 'with caustic with resultantformation"of'fthefsodium soap of the acid, and reacting ment 'andthe'liberation of vapors containingnaphthenic acid resulting from`decomposition of the copper naphthenate; the improvement which'comprises'separately withdrawing the copper compound and the liberatedfvapors containing the naphthenic acid resulting fromthe decompositionof the copper naphthenate from the zone of heat treatmentpassingwithdrawn vapors into intimate f contact with caustic withresultant formation of sodium naphthenate; reacting thesodium'naphthenate so formed With acopper" sal-tto form cupricnaphthenate and using the thusformed cupric naphthenate as the sourcematerial ofthe copper naphtlienate used -in the treatmentof furtheramounts of oil.

3. In'the process of treating petroleum oilwith a' cupric soap ofawater-insolubleorganic acid forthe' fiii'ation of sulfur compoundscontained thereininwhich the cupric soap is introduced'v into theoil'and the oil subsequently is suiojectedY to heat treatment and theliberation ofvapors containing' the water-insoluble organic acid re-vsulting from decomposition ofthe cupric soap; the improvement whichcomprisesv separately withdrawing the copper compound and the liberatedvapors containing the Water-insoluble or' ganic acid resulting from thedecomposition ofV the cupric 'soap 'from `the Zone of 'heat treatmentpassing withdrawn vapors into intimate contact with caustic withresultant formation of the sodium soap of the acidj and reacting thesodium soap of the acid" so formed with copper sulfate' to form thecorresponding cupric soap, and returning the thus' formed cupric soapfor the treatment of further amounts of petroleum oil.

4; In'th'eprocess of treating petroleum'oil witha cupric soap of aWater-insoluble organic acid for the xation'of sulfur compounds'contained therein' in which the cupric soap is introduced into the oiland the oil subsequently is subjected toheat treatment and theliberation of vapors containing'a water-insoluble organic acid result-`l0 forithex'ation of sulfur compounds contained: therein vinwhicn thecopper soap is introduced? into the-foil and the oil subsequently issubjected` to' -heat y treatment and theliberation 'i of vapors'in'gL-from :decomposition` of r thezfcuprio soap :the c improvement lwhich f comprises"separately'vy Jvvitha: drawing-the .copperfcompoundand the liberated.; vapors containing@ the Water-insoluble'v organicoacidi'esulting from" the decomposition" of other cupric soapfrom thezoneof heat treatment pass ing. withdrawn vapors `into' intimatecontact'witlr. molten f caustic with'y resultant formationt oix'theysodium; soapofthe acid,v and reacting the sodium;`soap-cf:theacid'fsolformed. with a coppersalt tow` form thecorresponding cupric soap, and returning/the .thus formedfcupric soap;for vthe treatment of ffu'rther amounts f of petroleum` oil,A

5. In the process of treatingrpetroleum Voil-Wiltli; a cupric soap of aWater-insoluble organic'acid for the iixation oi'sulfurcompounds..contained; therein iin-which. the. copper soapzisintroducedfl into the oil andthe oil subsequentlyfis subjected;tolieattreatment and the liberation ofvapols'-'- containingrthefwater-inso1ubleorganic acid reesultingiroml decomposition' or" thecupric'fsoapil tpe improvement' which comprises separatelyl withdrawingtlie cop-per compound-.andv-theliber i ated vapors contcin-ing` thewater-insolublefoimganic acidi-resulting from the:decomposition/of#4 thecupric soap from the zoneof heat treatment v passingV the Withdrawnvapors'into intimatefcon` tact with caustic with resultant for-mation'oithe sodiumsoap ofthe'acidireactingthe sodium soapl offthe acid .soformedr withaicopper salt-infant' aqueous mediumV in the presence of anoil in Which-f the: cupric soapLof-the acid *is soluble, Wherelo'yr` thecupric soap-'formed -is taken up by'and dis-f= solves in the oil-and theresulting solutiorriorms av-supernatant layer on the aqueousmediumg'andf' separatingthe'oil solution of thefcupric soap from"l theaqueous lmedium, and returning the f sepa-J- rated oilsolution of thecuprioy soap for treatment* of further amounts of petroleum oil."-

6i vIn the process of treatiirgpetroleum 'o-ilvvitli' a copper soap ot'aWater-insoluble organic acid* for-the xationof sulfur compoundscontained'l tlierein-invfhich the copper soap is introduced* intotheoilfand the oil subsequentlyis' subjected" toy heat treatment withthe liberation -of vap'ors` contain-ing the Water-insoluble 'organicacid"'re''- suitin'g from' decomposition of the copper soapi' andapoppercompoun'd; the improvement which" comprises'converting the coppercompound'to a" copper salt, passing"liberatedvapors containing? the-Water-insolub1e organic acid into intimate f contact With caustic withresultant formationof the sodium soap of theacid, reacting the sodium"soap so formed with the copper salt'iormed from the separated `coppercompound to form the'corresponding cupric soap, and using the thusformed" cup-ric soap asthe source material 'othecopp'er soap used in'the treatment of further amounts" of petroleum'oil.

Y. in the process of treating' petroleum oil with" a copper soap ofiaWater-insolublerorganic acid. for the xaton o'sulfur compoundscontained. therein in which the copper soap is introduced'into the oiland the oil subsequently is subjected' to'h heat 'treatment with theliberation tof vapors coni taining the 'waterlinsoluble organicacidresult-r ing from decomposition of the copper soap and av-coppercompound; theimprovement which comprises converting thecopper compoundtoV acop- 'per salt, passing liberated vapors containing the 'yWater-insoluble organic" acid' into intimate con;` tact With molten'caustic' with resultant 'formationof'the sodium soap ofthe acid,reacting the" sodium' soap4- so formed with the copper"sali."v

' formed lfr'omthe separated copper compound to" form` the correspondingcupric soap, and using the thus formed cupric soap as the sourcematerial of the copper soap used in the treatment of further amounts ofpetroleum oil.

8. In the process of treating petroleum oil with cupricnaphthenateforthe fixation of sulfur compounds contained therein in which cupricnaphthenate is introduced into the oil and the oil subsequently issubjected to heat treatment with the liberation of vapors containingnaphthenic acid resulting from decomposition of the cupric naphthenateand a copper compound; the improvement which comprises converting thecopper compound to a copper salt, passing liberated vapors containingnaphthenic acid into intimate contact with caustic with resultantformation of sodium naphthenate. reacting the sodium naphthenate soformed with the copper salt formed from the separated copper compour' toform cupric naphthenateand. returning the cupric naphthenate for thetreatment of further amounts of petroleum oil.

9. In the process of treating petroleum oil with a copper soap of aWater-insoluble organic acid for the nxation of sulfur compoundscontained therein in which a copper soap is introduced into the oil andthe oil subsequently is subjected to heat treatment with the liberationof vapors containing the water-soluble organic acid resulting fromdecomposition of the copper soap and a copper compound; the improvementwhich comprises passing liberated vapors containing the water-insolubleorganic acid into intimate contact with caustic with resultant formationof the sodium soap of the acid, converting the copper compound. to acopper salt, reacting the sodium soap with the copper salt formed fromthe separated copper compound in an aqueous medium in the presence of anoil in which the cupric soap of the Awater-insoluble organic acid issoluble, whereby the cupric soap formed is taken up by and dissolves inthe oil and the resulting solution forms a supernatant layer on theaqueous medium, separating the oil solution of the cupric soap from theaqueous medium, and using the thus separated oil solution of the cupricnaphthenate as the source material of the copper soap used in thetreatment of further amounts of petroleum oil.

l0. In the process of treating petroleum oil with a copper soap of awater-insoluble organic acid for the fixation of sulfur compoundscontained therein in which the copper soap is introduced into the oiland the oil subsequently is subjected to heat treatment with thelibera-A tion of vapors containing the Water-insoluble organic acidresulting from decomposition of the copper soap and a copper compound;the improvement which comprises passing liberated vapors containing thewater-insoluble organic acid into intimate contact with caustic withresultant formation of the sodium soap of the acid, converting thecopper compound to copper sulfate, reacting the sodium soap, at anelevated temperature and with agitation, with the copper sulfate formedfrom the separated copper compound in an aqueous medium in the presenceof an oil in which the cupric soap of the acid is soluble, whereby thecupric soap formed is taken up by and dissolves in the oil and theresulting solution forms a supernatant layer on the aqueous medium, andusing the thus separated oil solution of the cupric naphthenate as thesource material of the copper lo' soap used in the treatment of furtheramounts of petroleum oil.

ll. In the process of treating petroleum oil with a copper soap of awater-insoluble organic acid for the fixation of sulfur compoundscontained therein in which the copper soap is in.- troduced into the oiland the oil subsequently is subjected to heat treatment and theliberaation of vapors containing the water-insoluble organic acidresulting from the decomposition of the copper soap, the improvementwhichy comprises withdrawing the copper compound resulting from theAdecomposition of the copper soap, separately withdrawing all of the oilvapors containing the water-insoluble organic acid, passing theseparated vapors into intimate contact with caustic with resultantconversion of the water-insoluble organic acid to the sodium soapthereof, separating the oil vapors freed from the water-insolubleorganic acid. fractionating the separated' oil vapors, reacting thesodium soap with a copper salt to form the corresponding cupric soapyand using` the thus formed cupric soap as the source materialA of. thecopper soap used in the treatments of further amounts of oil.

I2. In. the process. of treating petroleum, oils, with cupric`naphthenate for the iixation of sulfur compounds contained therein inwhich cupric naphthenate is introduced into thev oil and the oilsubsequently is subjected to heatv treatment with the liberation ofvapors containing naphthenic acid resulting from-the decomposiftion ofthe cupric naphthenate. the improve-1 ment which comprises withdrawingthe Acopper. compound resulting from the-decoI-npositionl of the, cupricnaphthenate, separately withdrawing all of the oil vapors containing thenaphthenic acid, passing the separated vapors into intimate conta'ctwith caustic with resultant conversion of the naphthenic acid to Sodiumnaphthenate, separating the oil vapors freed of the naphthenic acid,fractionating the separated oil vapors, reacting the sodium naphthenatewith a copper salt to form cupric naphthenate and returning the cupricnaphthenate for the treatment of further amounts of petroleum oil,

13. In the process of treating petroleum oils with a cupric soap of awater-insoluble organic acid for'the xation of sulfur compoundscontained therein in which the cupric soap is introduced into the oiland the oil subsequently is subjected to heat treatment with the liber`ation of vapors containing the water-insoluble organic acid resultingfrom the decomposition of cupric soap; the improvement which compriseswithdrawing the copper compound resulting from the decomposition of thecupric soap, separately withdrawing all of the oil vapors containing thewater-insoluble organic acid, passing the separated vapors into intimatecontact with caustic with resultant conversion of the water-insolubleorganic acid to the sodium soap thereof, separating the oil vapors freedof the naphthenic acid, fractionating the separated oil vapors, reactingthe sodium soap with a copper salt in an aqueous medium in the presenceof an oil in which cupric soap of the acid is soluble, whereby thecupric soap formed is taken up by and dissolves in the oil and theresulting solution forms a supernatant layer on the aqueous medium,separating the oil solution of the cupric soap from the aqueous medium,and returning the separated oil solution of the cupric 1l soap for thetreatment of further amounts of petroleum oil.

14. In the process of treating petroleum oils with a copper soap of awater-insoluble organic acid for the xation of sulfur compoundscontained therein in which the copper soap is introduced into the oiland the oil subsequently is subjected to heat treatment with theliberation of vapors containing the water-insoluble organic acidresulting from the decomposition of the copper soap; the improvementwhich comprises withdrawing the copper compound resulting from thedecomposition of the copper soap, separately withdrawing all of the oilvapors containing the water-insoluble organic acid, passing theseparated vapors into intimate contact with molten caustic withresultant conversion of the water-insoluble organic acid to the sodiumsoap thereof, separating the oil vapors freed of the naphthenic acid,fractionating,r the separated oil vapors, reacting the sodium soap at anelevated temperature and with agitation, with a copper salt in anaqueous medium in the presence of an oil in which the cupric soap of theacid is soluble, whereby the cupric naphthenate formed is taken up byand dissolves in the oil and the resultant solution forms a supernatantlayer on the aqueous rnedium, separating the oil solution of the cupricsoap from the aqueous medium, and using the oil solution of the cupricsoap as the source material for the copper soap used in the treatment offurther amounts of oil.

15. In the process of treating petroleum oils With cupric naphthenatefor the ixation of sulfur compounds contained therein in which cupricnaphthenate is introduced into the oil and the oil subsequently issubjected to heat treatment with the liberation of vapors containingnaphthenic acid resulting from the decomposition of the cupricnaphthenate and the formation of a copper compound; the improvementwhich comprises separating the copper compound and converting it tocopper sulfate, passing al1 of the oil vapors containing the naphthenicacid into intimate contact with caustic with resultant conversion of thenaphthenic acid to sodium naphthenate, separating the oil vapors freedof the naphthenic acid, fractionating the separated oil vapors, reactingthe sodium naphthenate, at an elevated temperature and with agitation,with copper sulfate formed from the separated copper product, in anaqueous medium in the presence of an oil in which cupric naphthenate isSoluble, whereby the cupric naphthenate formed is taken up by anddissolves in the oil and the resultant solution forms a supernatantlayer on the aqueous medium, separating the oil solution of the cupricnaphthenate from the aqueous medium, and returning the oil solution ofcupric naphthenate for the treatment of further amounts of petroleumoil.

CHARLES O. HOOVER.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 2,068,979 Fischer Jan. 26, 19372,091,239 Hall Aug. 24, 1937 2,113,496 Roon et a1 Apr. 5, 1938 2,273,263Happel et a1. Feb. 17, 1942

